How to restrict element selection when using the Shift key in WPF Diagram (SfDiagram)?

In the WPF Diagram, you can restrict element selection when using the Shift key by utilizing the PreviewMouseUp and PreviewMouseDown events. Within these events, you can disable the selection behavior by setting e.Handled = true based on the necessary conditions. We have provided the code snippet to achieve this.

Code Snippet:

// Here, diagram is the instance of the SfDiagram.

diagram.PreviewMouseUp += Diagram_PreviewMouseUp;

diagram.PreviewMouseDown += Diagram_PreviewMouseDown;

private void Diagram_PreviewMouseDown(object sender, MouseButtonEventArgs e)
{
   if (Keyboard.Modifiers == ModifierKeys.Shift)
   {
       e.Handled = true;
   }
}

private void Diagram_PreviewMouseUp(object sender, MouseButtonEventArgs e)
{
   if (Keyboard.Modifiers == ModifierKeys.Shift)
   {
       e.Handled = true;
   }
} 

Conclusion
I hope you enjoyed learning about how to restrict element selection when using the Shift key in WPF Diagram.
You can refer to our WPF Diagram feature tour page to learn about its other groundbreaking feature representations and documentation to quickly get started with configuration specifications.

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